I wish Passion was an option back when I bought the Shaft Me Keisler Perfect Fit tremec. I'm still working on getting the drive angles right. Although I now know there is no alternative other than to cut the crossmember and build a custom trans mount. BTW Silver Sport transmissions is the old Keisler and they have NOT corrected the issue with the angles- or will tell you that some of these cars, ( for some mysterious reason) will not have the right angles. You have to chop your car up to find out. Sure had the right angles with the 4 speed.

Even with a stock 4 speed, the angles could be off, that why there were special tools, and the service manual shows how to check, and correct it. And they sold shims for the job. I wonder if the OP ever decided what to do?

Oh sure. very few cars I've worked on didn't have the shims at the trans mount for setting the angles . Now it's much easier with digital levels it takes about 5 minutes to get the readings and figure out where the adjustments need to be made. not difficult at all, as long as there is room.